The present invention generally relates to reclosable plastic bags and, more particularly, to a method of applying a slider to a fastener-carrying web of plastic film.
In one method of making slider-operated reclosable plastic bags, a continuous fastener is sealed to opposing longitudinal edges of a folded web of thermoplastic film moving in a longitudinal direction. To form individual bags, the folded web is sealed at bag-width distances apart along side seals that are generally transverse to the direction of web movement. To facilitate opening and closing the fastener, sliders are applied to the fastener at bag-width distances apart either just before or just after the side seals are formed in the folded web. In another method of making slider-operated reclosable plastic bags, the sliders are applied to the fastener prior to attaching the fastener to the moving web. In each of the above-noted methods, the fastener is positioned relative to the moving web such that the fastener can be easily accessed and controlled for installing the sliders.
To make slider-operated reclosable plastic bags in which the fastener is buried within a header or pocket near the top of the bags, the fastener is initially sealed near a center, rather than an edge, of a web of thermoplastic film moving in a longitudinal direction. The moving web is then folded in half along a longitudinal fold with the fastener inside the web and proximate the fold. To form individual bags, the folded web is sealed at bag-width distances apart along side seals that are generally transverse to the direction of web movement. Unless sliders are applied to the fastener prior to attaching the fastener to the moving web, it is difficult to access and control the fastener for installing sliders and performing other fastener-related operations after the fastener is attached near the center of the moving web. Because the fastener is parallel and close to the same plane as the web, gaining access to the fastener for applying sliders becomes limited by the close proximity of the fastener to the web.
Accordingly, an object of the present invention is to provide a method of applying a slider to a fastener-carrying web of plastic film that allows the fastener to be easily accessed and controlled for installing the slider and performing other fastener-related operations after the fastener is attached to the web.
This and other objects are realized by the following method of applying a slider to a fastener-carrying web of plastic film. The fastener includes interlockable profiles and fins depending from the respective profiles. One of the fins is attached to the web of plastic film such that the profiles are immediately adjacent to the web. The fastener is folded away from the web about the attached fin such that the profiles and proximate portions of the fins are oriented at an angle, preferably about 90 degrees, relative the web. Because the profiles and proximate fin portions are oriented at an angle relative to the web, they can be easily accessed and controlled for applying the slider to the profiles and performing other fastener-related operations.